Most oil producing subterranean formations are characterized by pressurized gas. In some parts of the world hydrocarbon bearing formations have pressures sufficient to force liquid hydrocarbons (crude oil) to the earth's surface. In other parts of the world, the gas pressure is not sufficient to force liquid hydrocarbons to the earth's surface. However, in such formations, the presence of gas is nevertheless important since in many formations a gas drive is required to move liquid hydrocarbons from within the formation to the site of producing wells.
As crude oil is extracted from subterranean reservoirs, the gas pressures decrease. As the gas pressures decrease, frequently crude oil production rates fall. For these and other reasons, it has been found desirable in producing many subterranean formations to maintain a gas pressure within the formation.
Th characteristics of gas injected into a well can be critical. Water or free oxygen contained in gas can cause plugging of formations. Further, water or free oxygen can result in bacteria growth that can plug a producing formation.
Ideally, gas injected into a reservoir to augment the production of liquid hydrocarbons should be water-free. Therefore, when treating gas prior to injection, a most important step is to remove substantially all water.
The present invention provides a process for generating substantially water-free exhaust gas that is particularly useful for injection into hydrocarbon bearing formations.
Examples of the use of exhaust gas from an engine for industrial purposes and examples of the use of exhaust gas to augment liquid hydrocarbon production are found in the following United States patents:
[United States Patents]
U.S. Pat. No.InventorTitle1,868,755MountDehydrator1,945,407Adair et al.Process of Purifying Gases2,240,550Conlon, Jr.Methe of Returning Gas to Gas-Producing Formations2,825,408WatsonOil Recovery by Subsurface ThermalProcessing3,004,601BodineMethod and Apparatus for Augment-ing Oil Recovery from Wells byRefrigeration3,100,528Plummer et al.Method for Using Inert Gas3,137,344WiemerMinimizing Loss of Driving Fluids inSecondary Recovery3,381,523NettlesMethod and Apparatus for SupplyingGas Under Pressure3,653,438WagnerMethod for Recovery of PetroleumDeposits3,908,762RedfordMethod for Estabiishing Communica-tion Path in Viscous Petroleum-Containing Formations including TarSand Deposits for Use in OilRecovery Operations4,324,291Wong et al.Viscous Oil Recovery Method4,325,432HenryMethod of Oil Recovery4,533,374HaagMethod for Reducing Air Pollution4,546,829Martin et al.Enhanced Oil Recovery4,593,763BurkeCarbon Dioxide Well InjectionMethod4,891,939BrighentiSystem for the Cryogenic Processingand Storage of Combustion Productsof Heat Engines5,232,049Christiansen et alSequentially Flooding a SubterraneanHydrocarbon-Bearing Formation witha Repeating Cycle of ImmiscibleDisplacement Gases5,988,280Crawford et al.Use of Engine Heat in Treating aWell Bore6,039,116Stevenson et al.Oil and Gas Production with PeriodicGas Injection